Municipal Secretary Sajid Javid said yesterday he intended to agree to a proposal from the district council to create a nationwide unitary council.
In a joint statement, the council members of Aylesbury Vale, Chiltern, South Buckinghamshire and Wycombe said: "Although we are extremely disappointed, the decision we are making is not set in stone, and we will give the State Secretary the best possible representation this decision is not the right one.
"We do not believe that this decision is in the best interests of our residents, businesses, community groups, councilors, and various other stakeholders throughout the county. Because of our own commitment, we do not believe there is strong local support. "
The districts had made a rival proposal that Aylesbury Vale would become one unit and the other three councilors would form another.
They said that this is evident in the differences in the economy, jobs, growth and housing markets throughout the county.
"One big unit will mean big opportunities are missed in these areas, and a single size for all models does not mean the best deal," they said.
"We are also questioning the savings that the single consistent model should deliver."